Problems with synchronization

Hey guys,

I'm having problems with the synchronization of a video I have to make. I have two different tracks. One of them comes from the camera, and the other one from an audio recorder. The point is that the last one is separated in two pieces, and there is a three-minute silence between them. They told me that during the recording, a man accidentally hit the stop button. I have tried to automatically synchronize the video by selecting first one track and then the other, but it doesn't work. The first part is correctly synchronized, but the second part is not. I have also tried to merge the two parts and to synchronize with the track of the camera, but it doesn't work either.

How can I fix it?

I would really appreciate your help...